19/78 SUREWAVE SFC USER MANUAL
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Operating principle
Refer to Figure 5-1: SureWave SFC SLD. The SureWave SFC employs Power Electronics Building
Blocks (PEBBs) in sets of two. The PEBB connected to the incoming utility is configured as an
active rectifier, which converts the incoming AC to DC. The PEBB connected to the load func-
tions as an inverter, to provide the load with clean power at the required voltage and frequency.
The PEBB pairs are then paralleled to give the required output rating, up to a maximum of
2.25MVA at 480Vac output. More than one SureWave SFC may be connected in parallel if the to-
tal required rating exceeds 2.25MVA.
The output of the SureWave SFC is at a fixed frequency and voltage, to suit the load require-
ments. Thanks to the double conversion architecture, the output voltage is tolerant to signifi-
cant voltage distortion and transients from incoming voltage.
5.2.1 Generator mode
In generator mode (VGen) the SFC emulates the behavior of a real rotary generator and thus in-
teracts with the power system in the same way as a traditional synchronous machine. This be-
havior is achieved purely through power electronic control and there are no large spinning
masses.
In this mode the SFC can be configured to run as a standalone power source with tight tolerance
voltage and frequency regulation (Isochronous) for a fixed application or as a power source run-
ning in parallel with other generators with voltage and frequency droop enabled.
In generator mode the bump less load transfer to and from another generator or generators.
The system can also synchronize to an external bus to connect another node to the output of
the SureWave SFC.
PEBBs
SureWave SFC
UC
Controller
GDM
Output Isolation
Transformer
V/F
Figure 5-2: SureWave in Generator mode
